Here are some interesting facts to include:

1) That there is a lake in the crater and how big the lake is.
2) When the last time was that it erupted.
3) When each cone was formed.
4) What kind of volcanic rock it is made of.
5) How volcanoes erupt in different ways – how a volcano "works"
6) Why volcanoes exist in the first place.
7) Why volcanoes are only in certain places and are not everywhere.

Things like that.

Hope that helps!
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